Using 100LL in small engines

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I tried searching but the maximum date range is 1 year. Are there any detrimental effects in using 100LL in engines other than chainsaws....typically engines with valves? The engines in question are the 4-mix in the BR600 & KM110 powerhead. Briggs 8HP horizontal shaft in a Trac Vac Kawasaki 15HP FH430V in my riding mower Vanguard 6HP in my pressure washer. The one engine I'm most concerned with is my 20HP Honda Twin in my generator, GX620. I'm not dead set on using the 100LL in these, especially the generator but want to ask about any issues I may have since they are not terribly high in compression. I did use the avgas in my KM110 and after a tankful it does run fine after I leaned it out slightly. All tips and criticism appreciated.
 
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Those already are designed with hard valve seats, so i'm not sure the lead with help. It won't hurt, but i see no advantage other than perhaps the chainsaw. Higher octane seems to so better in 2 strokes.
 
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I used to run 100LL in an old ironhead sportster...the chrome drag pipes would lose all the bluing and turn the prettiest shade of gold. That engine loved it.
 
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100LL is a very high quality fuel. Interestingly, today's 100LL is very likely to be 100VLL (very low lead) . The FAA has allowed manufacturers to produce 100LL with significantly lower lead levels, as long as it meets specification, which it does. There is no issue with using Avgas in small engines. In fact, many 2 stroke engines last longer with leaded fuels. In particular, the connecting rod "big end" bearing lifespan is significantly improved with leaded fuels. An added advantage is the fact that 100LL lasts nearly forever. So, it won't gum up your carburetors. Use it with confidence, including in your chainsaws. About the only issue I've ever had using 100LL, is the fuel petcock on my KTM 380EXC dried out after 10 years.
 
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Originally Posted By: i6pwr
I tried searching but the maximum date range is 1 year. Are there any detrimental effects in using 100LL in engines other than chainsaws....typically engines with valves? The engines in question are the 4-mix in the BR600 & KM110 powerhead. Briggs 8HP horizontal shaft in a Trac Vac Kawasaki 15HP FH430V in my riding mower Vanguard 6HP in my pressure washer. The one engine I'm most concerned with is my 20HP Honda Twin in my generator, GX620. I'm not dead set on using the 100LL in these, especially the generator but want to ask about any issues I may have since they are not terribly high in compression. I did use the avgas in my KM110 and after a tankful it does run fine after I leaned it out slightly. All tips and criticism appreciated.
Don't do that. You will have messed up sparkplugs, sticking valves and eventually, a burned valve. That's my personal experience. 100LL is not low lead. It has something like 4 times the lead that was ever used in auto gas. It is nasty stuff and shouldn't be used in a modern IC motor. I don't know what your cost for 100LL is, but locally, it's $6/gal. Wayne
 
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Originally Posted By: Oldmoparguy1
Originally Posted By: i6pwr
I tried searching but the maximum date range is 1 year. Are there any detrimental effects in using 100LL in engines other than chainsaws....typically engines with valves? The engines in question are the 4-mix in the BR600 & KM110 powerhead. Briggs 8HP horizontal shaft in a Trac Vac Kawasaki 15HP FH430V in my riding mower Vanguard 6HP in my pressure washer. The one engine I'm most concerned with is my 20HP Honda Twin in my generator, GX620. I'm not dead set on using the 100LL in these, especially the generator but want to ask about any issues I may have since they are not terribly high in compression. I did use the avgas in my KM110 and after a tankful it does run fine after I leaned it out slightly. All tips and criticism appreciated.
Don't do that. You will have messed up sparkplugs, sticking valves and eventually, a burned valve. That's my personal experience. 100LL is not low lead. It has something like 4 times the lead that was ever used in auto gas. It is nasty stuff and shouldn't be used in a modern IC motor. I don't know what your cost for 100LL is, but locally, it's $6/gal. Wayne
+1 I would use regular 87 octane with marine Sta-Bil in the fuel.
 
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high revving engines don't seem to like 101LL as much, seems to burn too slow. Other than that the big advantage of it is that it has a very long shelf life and no ethanol to absorb water and eat your fuel system parts up. If you have access to it, go ahead and run it in your stuff. You might get some deposits on the spark plugs but other than that your carb issues should go away. Do NOT run it in anything with an exhaust scrubber or catalytic converter, it will destroy them pretty quickly.
 
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Originally Posted By: Oldmoparguy1
[ Don't do that. You will have messed up sparkplugs, sticking valves and eventually, a burned valve. That's my personal experience. 100LL is not low lead. It has something like 4 times the lead that was ever used in auto gas. It is nasty stuff and shouldn't be used in a modern IC motor. I don't know what your cost for 100LL is, but locally, it's $6/gal. Wayne
Not true on all counts. 100LL "CAN" have a maximum of 2gm TEL per gallon. However, you will not find 100LL with that level of TEL today. As I mentioned above, much of the 100LL available here in the USA is actually 100VLL, with less than 0.5gm TEL per gallon. Plug and valve problems are a non issue.
 
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Originally Posted By: flacoman
Is there any ethanol in it??
NO Ethanol in LL100 That's the primary reason it's so poplar for 2-stroke applications, performance 2 strokes will not tolerate any water. All of my outdoor power equipment is Husqvarna and includes 4 chainsaws, 2 blowers, 2 string trimmers, and power hedge trimmers. My 1 string trimmer is 14 years old and I've never even pulled the spark plug out of it and it starts 2nd pull every time. I mix the LL100 with Klotz R50 at 50:1 very precisely and never worry. No need to drain the tanks or replace the fuel line every year. It is to expensive to run in my lawn mower and that gets used enough that I don't worry about water in the fuel. At my local airport it's as simple as walking in the flightline with my gas can, insert credit card, then when the machine ask for a tail # I input "cash" then fill my can.
 
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Originally Posted By: Cujet
Originally Posted By: Oldmoparguy1
[ Don't do that. You will have messed up sparkplugs, sticking valves and eventually, a burned valve. That's my personal experience. 100LL is not low lead. It has something like 4 times the lead that was ever used in auto gas. It is nasty stuff and shouldn't be used in a modern IC motor. I don't know what your cost for 100LL is, but locally, it's $6/gal. Wayne
Not true on all counts. 100LL "CAN" have a maximum of 2gm TEL per gallon. However, you will not find 100LL with that level of TEL today. As I mentioned above, much of the 100LL available here in the USA is actually 100VLL, with less than 0.5gm TEL per gallon. Plug and valve problems are a non issue.
Well, that's good to know. It's been a few years ago. We had a 172 and 2 supercubs for traffic watch and banner tow. 9/11/01 put us out of business. Thanks, Wayne
 
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Originally Posted By: 1foxracing
Originally Posted By: flacoman
Is there any ethanol in it??
NO Ethanol in LL100 That's the primary reason it's so poplar for 2-stroke applications, performance 2 strokes will not tolerate any water. All of my outdoor power equipment is Husqvarna and includes 4 chainsaws, 2 blowers, 2 string trimmers, and power hedge trimmers. My 1 string trimmer is 14 years old and I've never even pulled the spark plug out of it and it starts 2nd pull every time. I mix the LL100 with Klotz R50 at 50:1 very precisely and never worry. No need to drain the tanks or replace the fuel line every year. It is to expensive to run in my lawn mower and that gets used enough that I don't worry about water in the fuel. At my local airport it's as simple as walking in the flightline with my gas can, insert credit card, then when the machine ask for a tail # I input "cash" then fill my can.
+1 I have been using it for YEARS, in my own equipment and in my customer's equipment (I NEVER get a come-back when I use it). Avgas is far-and-away the best gas to use in ANYTHING that doesn't have a catalytic converter. It will NOT harm your engine in any way. It is, in fact, beneficial for both 2 and 4 cycle engines, and you will never have to worry about it getting old and gumming things up. It is GREAT for old pre-catalyst collector cars. If you have ready/easy access to it and don't mind paying the higher price, use it with confidence!
 
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i6pwr

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Originally Posted By: 1foxracing
I mix the LL100 with Klotz R50 at 50:1 very precisely and never worry. At my local airport it's as simple as walking in the flightline with my gas can, insert credit card, then when the machine ask for a tail # I input "cash" then fill my can.
I haven't used the Klotz but for the saw I wanted to lean towards something with castor but the little bit I have researched about the R50 is that it is a great for those applicatons. My local powersports dealer had the Motul 800 and I have started using that and so far so good, I'm mixing that 40:1. I feel better about the avgas now, good to hear the lead is reduced. My local airport sells it around $6.35/gal.
 
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Originally Posted By: 1foxracing
At my local airport it's as simple as walking in the flightline with my gas can, insert credit card, then when the machine ask for a tail # I input "cash" then fill my can.
I've wanted to mess around with 100LL for years but never gathered up the strength to deal with possible security nuts at the airports. Plus easy access, now, to E0 kinda took the wind out of the sails. I see a local airport has it for $4.90. About $.75 more than the E0 gas which I really don't trust. It possibly sits around in the tanks for longer than it should. I may have to call them and see what's up.
 
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I have a KM110R, I run Ethanol-free gas in it. It runs much better on E-free and Stihl Platinum oil than E10 mix. I know because I had to make mix a gallon of E10 in desperation and couldn't switch back fast enough. As for small engines in general, the newer 4-mix and Strato designs usually have no catalyst in the muffler and run OK on 100LL. Older 2-stroke designs still in production usually have a catalyst (and lately, capped carb mix screws). If it has a Cat muffler, even Low Lead gas will stuff it up after a while. Anyway I strongly recommend E-free 89 octane. Higher octanes are just a waste of money. If you read your small power engine manual, chances are good that it says to use 89 octane. http://puregas.org
 
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Originally Posted By: hatt
Originally Posted By: 1foxracing
At my local airport it's as simple as walking in the flightline with my gas can, insert credit card, then when the machine ask for a tail # I input "cash" then fill my can.
I've wanted to mess around with 100LL for years but never gathered up the strength to deal with possible security nuts at the airports. Plus easy access, now, to E0 kinda took the wind out of the sails. I see a local airport has it for $4.90. About $.75 more than the E0 gas which I really don't trust. It possibly sits around in the tanks for longer than it should. I may have to call them and see what's up.
I use a local municipal airport and there is no security at all. 4' tall fence with a walk through man gate that is never locked. I'm sure if you went to Miami international then you might have a problem... I've never once been questioned or even approached in the years I've been doing it. If anyone ever did ask you you can tell them you have a ultralight at home. I've been riding 2 stroke motorcycles since 1974 (both on & off-road models) and have always used Klotz 2 stroke oil. Many years ago I ran low on Klotz and put Amsoil 2 stroke in my 1973 H2 750, the motor seized in 7 miles and I haven't touched anything Amsoil since.
 
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Please guys, this fuel and its exhaust is quite unhealthy. Do you really want to inhale this lead and perhaps use it close to say growing vegetables that your kids will eat? 0.5% lead and it is not airborne for very long, it settles on the ground around your equipment and it won't vapor off. And what for? You don't trust gasoline??? COME ON!!! This fuel is basically required only for old WW2 aircraft, not lawn equpiment. I am not trying to be disrespectful, please think before here. Kids become stupid if exposed to lead, grown ups get sick. Do some pros and cons.
 
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I think you may be overreacting. The amount of lead released is going to be minimal. Regular gas is fine if you use in a timely manner. Problem is that people with a lot of OPE probably don't use all of it all the time and don't want to drain carbs every time they shut it off.
 
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Avgas used in small quantities in small engines isn't going to cause a health risk to small kids. 100LL is the only fuel approved for use in piston powered aircraft of any vintage as 80/87 and 115/145 octane fuels aren't being produced. I've used avgas mixed 50/50 with E0 premium with good results in my small engines as avgas has a shelf life of a couple of years.
 
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